Fast355

iTrader: (2)

Just wanted to let everyone know what the CCC Q-Jet setup that I recently tuned was able to make. 287 RWHP/ 335 RWTQ on a 355 vortec with a ZZ4 cam. The engine was a stock L31 with a ZZ4 cam, heads modified for the lift, and edelbrock TES exhaust system including headers (was on the stock 305 too). The engine was not in a F-car rather a 1987 Monte Carlo SS. The setup is running a 1228330 ECM from a 1988 Cadillac 307 Y and a custom chip by me. The EGR is turned off in the calibration as is the emissions air pump. Its not smog legal currently here, but passed the dyno inspection easily. With the GMPP Q-Jet intake it could easily be converted to use the EGR. The air pump was eliminated because it was in the process of locking up and we went to a serpentine belt accessory setup from a B-car. It runs a 350 knock sensor and knock module from a 1989ish 350 TBI truck. The driveability is flawless in open loop and closed loop. It also pulls hard from off-idle all the way to redline, regardless of throttle position. A few changes were made to the carb, installed larger primary jets from a 350 van, cut transition slots into the front of the air valves (3/8" long by 1/4" deep with the secondary acceleration port centered within ), roughened the bottem edge of the air valve (these steps will ensure a great 2-4 barrel transition rather than a bog), and tweaks to idle mixture screws and idle air bleed. The Monte Carlo with a 2,000 rpm stalled 200r4 and 3.73 gears is getting 16 mpg city, 25+ mpg on the highway and runs low 13s at the track.

Guro 305

Got pix?

Sonix

iTrader: (1)

Very nice!
Yea, a pic of the modified air valves would be nice, although I can imagine.
I can't quite picture this though:

five7kid

iTrader: (14)

Similar to my set-up, although no PROM tuning or q-jet tweaks have been done. I haven't run it at a sea level track, but when I drove it once at lower elevation it didn't seem to suffer from the stock LG4 primary jets. At WOT, the carb basically operates the same as a non-feedback q-jet.

I could use more stall, and don't have that much gear. Not sure what that Monte would weigh, the Camaro is at 3550 lbs with me going down the track (about 3500 lbs with my son driving).

I'm seriously considering Vortec heads, with Performer Vortec intake manifold. I believe they would improve it a little. May wait until the 383 goes in, though. . .

Fast355

iTrader: (2)

Here you go, most of the roughness was added to the back side of the air valve, but I don't have a picture of it. The picture shown is actually from another website where I got the idea from. I had seen the acceleration slots in pontiac air valves, but never knew why they were there. They DO work though. If you open the secondary air valve of a Q-Jet and look right to the front of where they cut out the small section of air valve, you will see a tiny passageway. This tiny passageway serves as an accelerator pump for the secondary side. Normally this passageway recieves a strong vacuum the second the air valve starts to move. This actually causes a momentary lean spike and helps contribute to the "quadrabog". With the slots cut into the air valve, the airflow starts to pull fuel out of the passageway, before the air valve even begins to open. This starts the fuel flowing as the air starts and helps prevent the lean spike. The throttle response when the secondaries are kicked in is drastically improved. This modification should work for everyone. I even did it with the stock 305 in my van back when I was still running the Q-Jet.

Sonix

iTrader: (1)

Oh yea, i've heard of this mod, but never saw anyone on here do it.
Rock on! Will go out to the garage to do that ASAP!
Weird 'roughing up' on the other side. Maybe i'll get a big file and try to do something like that...

Fast355

iTrader: (2)

I used an electric engraver to do mine.

Guro 305

Are those just little slots cut out in the back of the secondaries? Can't really tell much from glare on the pix.

whiley

interesting,

so your speaking about the (passageways) small pin size holes located just above the secondary air valve flaps?

so there is a small amount of vacuum/draw, being sensed by the pin holes/passageways, prior to the secondary air valve flap opening

does the modification need to be that large a cut out to work?

what is the function of the serated edge on there?

also, the roughness, do you mean just that the smooth surface is roughened (sand-paper, etc)

whats the function of that?

ur7x

iTrader: (2)

any chance you would want to PM me or email me your tune?

I'm trying to run almost the exact same tune on a Olds 355 with zero success.

Fast355

iTrader: (2)

Post everything you know about the Olds 355, the carb, etc. I will definately try my best to help you get it going.

ur7x

iTrader: (2)

Cool thanks for the offer,

It a 30 over 1975 Olds 350 (355)
9.55:1 CR Speed Pro Flat Tops
CCC Carb and Distributor
Computer friendly "baby" 60801 Voodoo Cam with matching springs
Advertised Duration (Int/Exh): 256/262
Duration @ .050 (Int/Exh): 213/219
Gross Valve Lift (Int/Exh): .485/.499
LSA/ICL: 112/108
Comp Cams Adjustable Roller Rockers
Holley Street Dominator Intake (port matched, and plenum opened up to match Q-jet spread bore)
"N" Crank (like there is any other kind)
#8 Heads ported, polished, tear dropped guides with BBO sized Valves
2.00" intake and 1.65" exhaust
Double full roller timing chain

Stock 200-4R tranny and stock 373 read.

Fast355

iTrader: (2)

What is it doing?

Kevin84Z28

iTrader: (3)

Very interesting...Can you answer the questions whiley posted? I'm interested in knowing also. Thanks.

ur7x

iTrader: (2)

refusing to idle below 900 rpm and only pulls 13-14" of vacuum at idle...
Lunati's help line assures me that I should see AT LEAST 18" of vacuum at a 600-700 rpm idle with the the cam that I picked.

I spent all summer looking for a vacuum leak... and have had no luck... a Mechanic at work thinks that I have over tighten my rocker arms and this is causing a "blow back" leak as the intake valves are held open too long... maybe... but I doubt it...

The cam was installed "straight up" not "advanced 4*" as per the cam card... Yes I degreed the cam... I noted this error, thought that was how it should be and buttoned up the motor (aka STUPID)

This winter I plan to rip the front of the motor apart and triple check the cam timing...and fix it. Though everyone tells me that a 4* cam retard shouldn't cost over 4" of vacuum at idle...

Compression testing also points to something other then overly tight rocker arms since it make a really nice and even 170psi on three cranks on each hole. If the intakes were leaking the compression test should be crap... right?

The CCC system worked AMAZING on the stock Olds 307... great mileage, good performance and Zero issues with emissions testing.

I did replace the secondary rods on the Q-jet to 350'ish "AH" rods these are very close to the rods GM recommended for the HO 350 Camaro swap.

I have three CCC computers for this car.. The untouched stock one with the stock Vin9 Prom in a stock 1227301 (it runs happy with no codes in spite of the really crappy vacuum signal) and I also have a 1228079 (from a 87 Monte SS) and a 1228330 from a 1989 Vista Cruiser. We have a chip burner at work so making custom chips is not an issue (or a big expense for me).

Oh one more tidbit... when I hook up the ol' dwell meter to the carbs test port... At idle it runs a 8-10* of dwell... AKA Full Rich.. as I rev her the dwell speeds up (leans out) and then goes back to fill rick at idle.

If you can fix it... the beer/scotch/tequila is on me!

Fast355

iTrader: (2)

Are you sure you have the timing properly set via the OE recomeended procedure. The oldsmobile V8s used a unique method to set the timing. IIRC you have to enter field diagnostic mode with a paper clip (Diagnostic terminal grounded, engine running, like you are checking for codes) and set the timing to 20*BTDC in Field Service mode. Setting it any other way will not allow the engine to run properly. You may have to cheat a little on the base timing if your calibration was setup for a swirl port head 307. Older heads generally require you to run 4-6* more timing across the board than the swirl ports.

90% of your fuel system problems stem from the primary side of the carb. If the ECM is richening the mixture, there is usually a reason. Keep in mind it could be the overlap of the cam pushing 02 past the 02 sensor, a bad 02 sensor that is not switching properly, or even an exhaust leak allowing 02 to be sucked into the exhaust and past the sensor. Those stock 1 wire unheated sensors only last about 15K miles or so before there performance starts to signifigantly drop.
.
You will probably have to drill out the idle channel restrictors and the opening at the idle mixture screw. You have to be careful here and go in small increments. The 403 I put in place of my 307 in my Cadillac required me to go completely through the CCC Q-jet.

ur7x

iTrader: (2)

1) Timing... Yes I set the timing by shorting out the ALDC as per the FSM and set it to a stock 20* BTDC. I did manage to pick up 2" of vacuum if I advanced the timing even more to 22-25* and It ran a little better... (back to my f'ed up cam install therory?) The problem with 25* of initial advance is that it builds so much compression that my stock starter will not turn her over... I have a summit high torque unit ready just in case...

2) Exhaust leak... The AIR pump is gone and the #8 heads have no AIR holes, I'm using the stock 1975 Drivers exhaust manifold and the stock 1987 Passengers side unit... This allowed me to delete the heat riser valve... which is fine since the car is a sunny day only vehicle.

3) O2 sensor... it is the stock unit and has at least 90,000 miles on it... But it did work perfectly before the swap and I have emissions testing numbers that are better then my wife's 99 EFI 4-Runner.

4) Rich/Lean... Off idle the drivablity of the new motor is quite good... And as soon as the MAP signal is around 20" (like when you just rev it...) the carb leans things out quite nicely... I know lots of guy who run these carbs on Chevy 350s without any carb modifications... If I do need to drill out the carb... then I might as well just switch to a "decomputered" option.

Do you think that having the cam accidentally installed with a 4* retard could be causing all of my problems? I have the gasket kit and over the winter I'm going to "have at it"... but I would be a little more motivated if I thought it might actually work.

trumps2000

iTrader: (2)

Hey stupid question, have you looked at the plugs? I went through this awhile ago, it had nothing to do with the carb. I had vacuum leaks, one through the intake gasket which would burn oil fouling plugs. I also need to disconnect everything but the MAP to find the other leak through the hoses.

ur7x

iTrader: (2)

Ya, all 8 plugs are nice and clean with light tan deposits. I checked them when I did the compression test.

FlippindaBird

iTrader: (10)

subscribing, i will be installing my stock 87 Qjet on top of a vortec headed 350 with a GMPP LT4 HotCam and a performer RPM intake w/ hooker 2055R's into a SLP Loud Mouth for 4th gens... 2600 rpm stall, 700r4 with transgo shiftkit, 3.42 gears, im guessing the car should be around 3400-3500 with me in it, ill be deleting the egr and air, dont have to pass emissions, its a cruiser/racer no DD... should have the thing installed this coming weekend, then im gonna go through the trouble shooting... the carb is TOTALLY STOCK so we will see how it goes, if its ok i will post here with concerns about the carb because it seems like you have a good grasp of whats gong on with these carbs, and i have never even turned the idle screw on one lol heres a link to my thread https://www.thirdgen.org/forums/engi...ml#post4723151

Camaro305SB

Dude, this thread is two years old, start a new thread if you encounter any problems. Good luck btw. I'm going to be using the stock CCC as well, soon as I get my hands on one. Oh, don't delete any emissions components - they aren't restricting any power trust me. Maybe the cat, in which case high flow units are damn cheap.

FlippindaBird

iTrader: (10)

yeah i dont read the dates, the RPM intake wont accept egr, and if it doesnt need it, why put it on?? the cat is hollow with a 3" pipe welded in there, it just looks like a cat, enough to get me through my countys PA inspection, so i can drive it to the track and around my comunity once in a while...

DoubleV

The stock chips in the ECM are calibrated for use with an EGR valve. If you delete the EGR and still run a stock chip, you can get part throttle pinging.

I've also heard removing the EGR on a Chevy CCC setup ( at least on a Monte ) will trigger the CEL. This doesn't happen with the Olds CCC setop. Go figure.

FlippindaBird

iTrader: (10)

then im gonna need a chip burned... anyone able to help me with that??

five7kid

iTrader: (14)

Only if you electrically disconnect the EGR solenoid. If you leave the solenoid electrically connected, no SES light.

DoubleV

Yes that is true ( or so I've heard ), but I've always assumed when people delete their EGR valve, it's usually because they want to get rid of the all the clutter under the hood, so the EGR solenoid is almost always dumped along with it.

Strange why the CEL light doesn't trip on an Olds ECM with the solenoid disconnected. I wonder why that is? Oh well, it is what it is.

naf

iTrader: (7)

Nor does it trip on an '87 Camaro ECM when disconnected. Been without it for six years now. Put the Vortec heads on in Summer 2004.

I have yet to try the '85 and '84 to see what will happen.

Sparkytfl

Removed the solenoid from my 85 (originally had the low output carb 305, now has vortecs so no egr) and had no problems. I actually left it plugged in and tied to the wire bundle at first because I thought it was going to throw some codes, but tested later and it was fine without.

Fast355

iTrader: (2)

I know this is an old thread, but I found out if you remove the solenoid, measure the resistance and put in a 1/4 watt resistor of a very similar resistance in place of the solenoid in the the connector, tape it up, and tuck it into the loom, it will run without codes an clean things up nicely. Same thing goes for the air solenoids.

Fast355

iTrader: (2)

I know this is an old thread, but I found out if you remove the solenoid, measure the resistance and put in a 1/4 watt resistor of a very similar resistance in place of the solenoid in the the connector, tape it up, and tuck it into the loom, it will run without codes an clean things up nicely. Same thing goes for the air solenoids.

Sparkytfl

Yes this thread is old. So old I dont even have the car anymore.

That does seem like a valid solution for the later cars. Earlier ones wont throw any codes anyway. I dont know what year things changed though.

FlippindaBird

iTrader: (10)

im about to find out with my 87 and then ill need more info on your fix ive deleted air and egr and i have no idea what your talking about wiring kills me LOL

scooter500

iTrader: (1)

I've been considering a vortec setup too (l31 long block). There is an EGR carb intake for vortec. No idea on performance characteristics.

GM Performance 12496820 - GM Performance Vortec Low-Rise Intake Manifolds

FlippindaBird

iTrader: (10)

yeah originally thats what i was gonna do, go street legal and keep the egr and air and everything, but it was 3x what i paid for my performer RPM